This happens every year. Water gets a bit low, people pray for rain as they are not catching coho. When the rain comes, the water gets high, the fish just shoot straight up to the hatchery.
Last year, I was lucky enough to get into a couple of fish on September 10th. Overnight, it rained heavily and by the morning of September 11th, the river was too muddy to catch fish. The fishing was poor for at least a week as most coho just ended up heading straight into the hatchery and upper river.

You can still successfully catch coho under low and clear water conditions, just have to walk more, and fish harder.